2016 AXE Element BBCOR Baseball Bat: L137D 2 5/8 Inch Barrel Diameter -3 Length to Weight Ratio One-Piece, Alloy Construction Mantic Alloy - High Strength, Military-Grade Formula Provides Maximum Durability for One-Sided Hitting AXE Grip - Ergonomically Designed for Better Control, Bat Speed, Comfort, and Safety